Volvo Ocean Race Research Supports Zero-Emission Shipping
As part of its research into zero-emission shipping, the Dutch research organization MARIN has performed calculations, model tests and measurements on the Simeon Tienpont, AkzoNobel Volvo Ocean 65 (VO65) racing yacht.
MARIN built a VO65 ship model and tested it in waves to help Tienpont and his team maximize their performance in the race. The work included numerical simulations, model tests and full-scale measurements onboard the VO65. It provided insight into the vessel's added resistance in waves which will give the navigator improved onboard performance prediction, enabling him to determine the fastest routes to the finish at any time during the race.
On Friday, Tienpont and his team visited MARIN to watch the model test demonstrations. “With their unique combination of computer calculations, model tests and onboard measurements, we will be able to get the final extra few percentages of performance out of our VO65 during the roughest times of the race,” said Tienpont.
The Volvo Ocean Race, starting in October, is the longest and toughest sailing event in the world. For MARIN, it fits perfectly with the organization's research on sail assisted propulsion and its ambition to achieve zero emission shipping. MARIN is able to independently predict fuel savings for wind-assisted ships compared to a conventional ship design, including the environment on actual routes, and to advise how savings can be improved. The issues of operability, compliance and safety that are related to wind-assisted ships, e.g. course keeping, non-steady roll angle and different ship motions, are considered.
The operational profile includes the dominant wind speed and directions on the intended routes. Important hydrodynamic choices are then made on whether to choose for relatively high stability (large beam, low draught), which sustains more wind power but also creates more drag, or a more slender hull, with less resistance that supports less wind assistance.
Once the main dimensions are set, hull form and appendages determine the ability to generate side force and steering balance. The forces determined using preliminary tools, CFD or model tests are used to create a speed-power prediction (commonly referred to as “PPP”: Power Prediction Program, in analogy to a “VPP” for pure sailing ships). The results show the required propulsion thrust or power for a certain speed as a function of true wind angle and speed. These results show ideal performance in calm water. In reality, the apparent wind angle and speed will vary depending on weather, operational conditions and the route. MARIN uses an in-house simulation tool to predict behavior over time.
MARIN research has contributed to the design of sailing cargo ships including the Ecoliner design as developed by Dykstra Naval Architects and sail-assisted ships including the Wind Hybrid Coaster that uses Flettner rotors.